This invention relates generally to the field of telephony, and more particularly to an improved telephone protector block for mounting protector modules for individual subscriber circuits.
In the area of individual subscriber circuit protector modules which are carried by protector blocks mounted on a main frame in a telephone central office, there has been continuous improvement in technology over the last decade, offering degrees of protection previously unavailable and presently required by the use of solid state technology in central office switching equipment. The usual carbon block protector units are supplemented by highly sophisticated gas tube and heat coil technology, the manufacturing cost of which has been reduced to permit widespread usage in the art.
Such improvements have been designed with a view toward incorporation into module housings generally used in the continental United States, which housings are of elongated rectangular configuration having five projecting pins on one end thereof which engage corresponding sockets in individual areas on an exposed surface of a protector block. These pins are arranged in a generally rectangularly shaped pattern, with the tip in, tip out, ring in, and ring out pins being disposed at the corners of the rectangle, the ground pin being disposed slightly laterally relative to one of the sides of such rectangle.
In attempting to export the above-mentioned improved technology to foreign countries, particularly in the Far East, difficulties have been encountered by reason of the fact that existing protector blocks in such countries are of such configuration that interconnection with domestic modules is not possible without resort to an adaptor to compensate for relative differences in pin and terminal location. Because of space limitations, the use of such adaptors, in some cases, is difficult, if not impossible. In such cases, it becomes necessary to replace the existing protector block with a suitable block accepting standard protector modules. Such replacement must permit interfacing with existing wiring leading from the block to other equipment.